nuttx/cache.h: fix the compile warning in sim when enable OpenAMP

/data/project/code/apache/nuttx/cmake_out/sim_server/openamp/libmetal/lib/include/metal/system/nuttx/cache.h: In function ‘__metal_cache_flush’:
/data/project/code/apache/nuttx/cmake_out/sim_server/openamp/libmetal/lib/include/metal/system/nuttx/cache.h:25:46: warning: unused parameter ‘addr’ [-Wunused-parameter]
   25 | static inline void __metal_cache_flush(void *addr, unsigned int len)
      |                                        ~~~~~~^~~~
/data/project/code/apache/nuttx/cmake_out/sim_server/openamp/libmetal/lib/include/metal/system/nuttx/cache.h:25:65: warning: unused parameter ‘len’ [-Wunused-parameter]
   25 | static inline void __metal_cache_flush(void *addr, unsigned int len)
      |                                                    ~~~~~~~~~~~~~^~~
/data/project/code/apache/nuttx/cmake_out/sim_server/openamp/libmetal/lib/include/metal/system/nuttx/cache.h: In function ‘__metal_cache_invalidate’:
/data/project/code/apache/nuttx/cmake_out/sim_server/openamp/libmetal/lib/include/metal/system/nuttx/cache.h:30:51: warning: unused parameter ‘addr’ [-Wunused-parameter]
   30 | static inline void __metal_cache_invalidate(void *addr, unsigned int len)
      |                                             ~~~~~~^~~~
/data/project/code/apache/nuttx/cmake_out/sim_server/openamp/libmetal/lib/include/metal/system/nuttx/cache.h:30:70: warning: unused parameter ‘len’ [-Wunused-parameter]
   30 | static inline void __metal_cache_invalidate(void *addr, unsigned int len)
      |                                                         ~~~~~~~~~~~~~^~~

Signed-off-by: Bowen Wang <wangbowen6@xiaomi.com>

Author: CV-Bowen

include/nuttx/cache.h

@@ -342,7 +342,7 @@ void up_disable_dcache(void);
 #ifdef CONFIG_ARCH_DCACHE
 void up_invalidate_dcache(uintptr_t start, uintptr_t end);
 #else
-#  define up_invalidate_dcache(start, end)
+#  define up_invalidate_dcache(start, end) ((void)(start), (void)(end))
 #endif
 
 /****************************************************************************
@@ -384,7 +384,7 @@ void up_invalidate_dcache_all(void);
 #ifdef CONFIG_ARCH_DCACHE
 void up_clean_dcache(uintptr_t start, uintptr_t end);
 #else
-#  define up_clean_dcache(start, end)
+#  define up_clean_dcache(start, end) ((void)(start), (void)(end))
 #endif
 
 /****************************************************************************